Electric-circuit breaker



E. M. MOLLEH.

ELECTRIC CIRCUIT BREAKER.

APPLICATION FILED AuG.2s. 1919.

PatentedSept. 27,1921.

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ELECTRIC cmcun BREAKER.

APPLICATION FILED AUG-28,1919.

Patented Sept. 27, 1921.

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ELECTRIC CIRCUIT BREAKER.

APPLICATION FILED AUG.28, I9L9,

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ELECTRIC CIRCUIT BREAKER.

APPLICATION FILED AUG-28,1919.

PatentedSept. 27, 1921.

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I E. M. MOLLER.

ELECTRIC CIRCUIT BREAKER.

APPLICATION FILED AUG.28. 1919.

Patented Sept. 27, 1921.

7 SHEETSSHEET I.

/I T'TURNE UNITED STATES PATENT "optics.

EDVARD M. MOLLER, OF JERSEY CITY, NEW JERSEYH ELECTRIC-CTBCUIT BREAKER.

To all whom it may concern:

Be it known that I, EDV RD M. MOLLER, a citizen of the United States,residing at Jersey City, in the county of Hudson and State ofNew Jersey,have invented certain new and useful Improvements in Electric- CircuitBreakers; and. I do hereby declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, and to characters ofreference marked thereon, which form a part of this specification.

This invention relates, generally, to improvements in circuit-breakers;and, the present invention has reference, more particularly, to thatclass of circuit-breakers foruse upon trolley or electric railway cars.

The present invention has for its principal objects to provide asimply-constructed tripping-mechanism in which a magnetically controlledtripping mechanism is released whenan excess charge of electricitypasses into and through the assembled devices and parts of the device orapparatus, thereby furnishing protection against too heavy overloads orgrounds, and short circuits which may occur in the car-equipment.

' Other objects of the present invention are simplicity of constructionof the mecha- 'nism; readiness of installation of the apparatus betweenthe trolley-cable and the controller, the apparatus being light inweight, and being of high capacity and most efficient in its operation.

i Still other objects of the present invention not at this time moreparticularly enumerated will be clearly understood from the followingdetailed description of the present invention.

With the various objects of the present invention in View, thesaidinvention consists, primarily, in the novel car circuit breakerhereinafter more fully set forth; and, the

present invention consists, furthermore, in

Specification of Letters Patent. Patented Sept. 27, 1921- Applicationfiled August 28, 1919. Serial N0- 320,508- v The invention is clearlyillustrated in the accompanying drawings, in which F1gure 1 is a plan ortop view of the cir-' cult-breaker embodying the principles of thepresent invention, the box or casing in WlllCh the mechanism is housedbeing represented in horizontal section; and Fig. 2 is a verticalsectional representation ofthe same, said section being represented astaken on line 2-2 in said Fig. 1, looking in the direction of the arrowas.

Fig. 3 is a similar sectional representation of the mechanism, saidsection being taken on line 33 in said Fig. 1, looking in the directionof the arrow y, the upper member of the box or casing, however, beingomitted from said view.

Fig. 4 is a plan or top view of the circuitbreaking mechanism, showingthe several parts thereof in their relative position, when the circuitis broken, said view being made on aslightly reduced scale, with the boxor casing-members omitted from said view; and

'Fig. 5 is a detail vertical sectional represen- I casing member; withthe mechanism removed therefrom; and Fig. 7 is a longitudinal verticalsection of the same, said section' being taken on line '77 in said Fig.6.

, Fig. 8 is a bottom view of the upper box or casing-member; Fig. 9 is aside elevation of the same, looking in the direction of the arrow a insaid Fig. 8; and Fig; 10 is a transverse vertical section of the same,said sec-- tion' being taken on line ,1010 in said Fig. 9. a

Fig. 11 is a plan view of the arcing box or element employed with themechanism; and Fig. 12 is van elevation of the same, looking in thedirection of the arrow u'in said Fig. 11. Fig. 13 is a plan view of theoverload or blow-out coil of'the circuit-breaker, the upper member ofsaid coil being omitted from said view; and Fig. 14 is a view of thesaid 1 coil, partly represented in elevation and partly shown invertical section.

Similar characters of reference are employed in all of the said abovedescribed views. to indicate corresponding parts.

Refering now to the several figures of the drawings, thereference-character 1 indicates the lowerbox or casing member of theapparatus, the same being ofany suitable configuration, comprising a top2 and bounding side-walls 3 andend-walls 4, all mounted upon a closingbase-plate 5, substantially as shown more particularly in Fig. 2 ofthedrawings, and the various members of the said box being made,preferably, of a material which is a non-conductor of electricity,.orbeing suitably insulated so as not to act as an electrical conductor.Suitably mounted above the top 2 of said lower box 10 having holes orperforations 11 for the attachment of the circuit-breaker in the desiredlocation upon a car, or other place of location.

Similarly,-within the interior of the upper box or casing-member 6, thelatter is provided with suitably disposed lugs, as 12, formed withinternally screw-threaded receiving sockets 13 for the reception of thescrew-threaded shanks of tightening studs or bolts 14 which are insertedinto and through tions 15 1n the top 2 of the lower box or casing-member1 for properly securing the two members'l and 6 together in operativerelation, as will be clearly evident. In one of its side-walls 8, theupper box or casingmember 6 is provided with suitabl disposed openings,as 16 and 17, and in its opposite side-wall the said box or casing-memer6 has an opening 18, the pur ses of which will hereinafter be moreforth. The said up r box or casing-member 6 is also PI'OVI ed withvalaterally ex-' tending partition 19 of the same material of which thebox or member 6 is made, said partition having an opening 20. To securethe base-plate 5 to said lower box or casingmember 1, the latter isprovided with suit-' ably disposed lugs, as 21, formed with internallyscrew-threaded sockets, as 22, for the reception of the screw-threadedshanks of studs or screws 23, which are inserted into and throughcorrespondingly located holes or perforations 24 in said baselate 5, asindicated more particularly in igs. 6 and 7 of the drawings.

The said up or box or casing-member 6 is also formed in one of itsend-walls 9 with an opening, as 25, see Figs. 1 and 2 of the drawings,into and through which extends and projects, as shown in said Fig.

roperly located holes or perforally set 2, a suitably formed arcing-boxor element I member 1, said screws 27 being insertedv through holes orperforations 28 in said topplate 2, and the screw-threaded shanks ofsaid screws 27 being screwed into the internally screw-threadedreceiving sockets 29 with which the partition 19 is provided.v Referringnow more particularly to Figs..

2, 3, 13 and 14 of the drawings, 'it will be seen, that disposed againstthe lower surface of said top-plate 2 is a layer of insulating material29, and secured against the latter, by means of a bolt or screw 30, is amagnetic field-pole-piece or element 31 of soft iron, said pole-piece orelement having a downwardly extending portion .32 terminating, near thebase-plate 5 and extending longitudinally within the lower box orcasingmember 1, in a carrier-member33. Suitably secured upon the freeend-portion of said carrier-member, by means of a screw 34 or in anyother suitable manner, is an upwardly projecting stem or rod 35 ofmetal, said stem or rod extending into and through a properly locatedhole or opening 36 in the top-plate 2, and being provided upon its upperpart, which is located within the upr box or casing-member 6, with anenargement, as 37, formed with a screwthreaded receiving socket 38, forthe pur- }sioses to be presently more fully described. urroundin thatportion of the stem ,or rod 35, withln the lower box or casing-member 1,and resting upon the carrier-member 33, is a tubular core 39ofsoft-metal, and concentric with this core is a coil-spool, as

40, said spool being made of. fiber "or other insulating material. Theoverload or blowout coil carried by said spool, consists of layers offlat copper 41'. alternating with disks or layers 42 of cement paper, orthe like, and 43 and 44 indicate the respective end terminals of the coper coil, said terminals -being respective y; rovided, with holes orperforations 45 an 46, in alinement vertically with corres ndinglylocated holes or perforations 4 and 48 inthe top-plate 2. Mounted uponthe up er surface of said top-plate, and locate within the up r box orcasing-member 6, are a pair 0 cable-receiving and clampin elements, as49 and 50, see Figs. 1, 2 and 3 of thedrawings, the said clampingelements being secured in place by means of screws 51 and52,'respectivel which are screwed into the screw-threade holes 53 and 54with which the top-plate 2 is provided, the cableclamping jaws of the.respective clamping elements 51 and 52 being, respectively, furtherprovided with binding or clamping screws or bolts 55 and 56. Extendingdownwardly from the res ective clamping elements 51 and 52, anprojecting into and through the respective holes or perforations" theirassembled relation by the usual arrangement of nuts, as 59 upon the saidcontact-lugs or studs 57 and 58, as will be clearly evident from aninspection of the drawings.

Referring now more particularly to Fig. 2 of the drawings, it will beseen, that there is mounted upon theupper end-portion of' theenlargement 37 of the previously-mentioned stem or post 35, a disk orplate 60, said disk or plate being held in place by a screw 61 which isscrewed into the receiving. socket 38, as indicated in dotted outline insaid figure. Suitably-mounted upon the upper surface of said top-plate2, by means of screws 62, or other suitable fastening vmeans, is a plate63, preferably formed with a reinforcing rib 64, and a pair of upwardlyextending members 65 and 66, respectively formed with bearing-portions67 and 68. The said plate 63 is also provided with a suitably disposedhole or perforation 69 through which the rod or stem 35 projects, withthe enlargement 37 of said rod or stem resting directly upon said plate,in the manner indicated in Fig. 20f the drawings. Os-

cillatorily disposed upon the enlargement 37 .of the rod or stem 35 isthe hub 70 of what is known as the switch-arm, said hub having an arm 71extending therefrom, said arm being providedat its*free end with abifurcated member 72, carrying a with a'roller74 mounted uponsaid pin.At right angles to said arm 71, or approximately so, are a pair of otherarms, as 75,

located one above the other, said arms 7 5' having angularly disposedperforated endmembers, as 76, carrying a in 77. Pivotally mounted uponthis pin 7 is a' contactlever or member, as 78, provided at one end witha clamping element 79, between the clamping members of which isdisposed, and securely clamped by means of a tightening bolt or screw80, the one end-portion of acopper series wire or cable 81, the otherend-portion of the latter being securely clamped between the clampingmembers of the, previously mentioned overload and blow-out coil-terminal49. The clamping element 79 of said lever or'member 78 is also providedwith a perforated portion 82 to which is attached the one end-portion ofa coiled spring 83, said spring having its other end-portion secured toa perforated lug 84 extending from the member 66 of the pin ,73

plate 63. Upon its opposite end, the said' contact-lever or member 78 isprovided with a post-like portion or extension, as 85, formed with anabutting off-set 86, and seated against said post 85 and its off-set 86,and secured in its position, by means of a bolt or screw 87, is a coppercontact-establishing member 88, having a contact-tip .89 thesurface-portion 90 of which is suitably curved or chamfered to provide agradual breaking surface and to prevent excessive arcing, as will.hereinafter be more fully set forth. Secured to saidcontact-establishing member, by means of the bolt or screw 87, andresting against the back of the contacttip 89 is an angular arcing hornor deflector, as 91. Secured upon the upper surface of the .top-plate 2,in suitable location, by means ofsc'rews 92, or in any'other suitablemanner, isa bar-like member or post 93, carrying a clamping element 94,between the clamping member of which is securely clamped by means of atightening bolt or' screw 95, the end-portion of a leading-in wire orcable 96, leading from the usual trolley-wheel.

This clamping element 94 is also formed with an abutting offset 97, and.seated against said element 94 and its ofi-set 97, and secured in itsposition, by means of a bolt or screw 98, is anothercontact-establishingmember 99, having a contact-tip 100, i

the surface-portion 101 of which is also suitably curved or chamfered',which under nor mal initial conditions is electrically in contact withthe contacting surface 90 of the contact-tip 89. Secured to saidcontact-establishing member 99, by means of the bolt or screw98, andresting against the back of mentioned arclng box 26, located in theendwall 9 of the upperbox or casing-member 6, the said box comprising abottom-member 104, ,a top-member 105, and intermediate sideswalls 106and 107, to which said members 104 and 105 are secured by means ofscrews 108. As shown in Fig. 11 of the drawings, the said arcing-box 26is usually provided with a receiving socket 109 into which is adapted tobe fitted a stud or post, as 110, connected'with and extending from alug or projection 111 with which the box or casing-member 6 is provided,substantially as illustrated in Figs. 8, 9 and 10, the purpose being toproperly locate and hold the said arcing box 26 in position. Locatedabove the top-member 105 of said arcing box 26 is a magnetic-fieldpole-piece or block 112 having an arm 113 the end-portion of whichextends along the inner surface of the ing engagement.

vided with a perforated lug 120, or other 'hold the same in place.

the hub-portion 117 of a pawl made in the manner of a bell-crank, saidpawl comprising an arm 118 formed with an off-set 119 with which theroller 73 of the arm 71, under normal initial conditions is in hold- Thearm 118 is also prosuitable means, to which is secured the, one end of atension spring121, said spring having its other end secured to aperforated lug 122 extending from the hub-portion 123 of a handle-lever124, as shown in Figs. 1 and 4 of the drawings, the hub" 123 of saidlever being mounted upon the enlargement 37 of the stem or rod35,'andthe said lever extending into and through the opening 18 in theside-wall 8 of the box. or casingmember 6; asv shown. The said'pawl alsocomprises another arm 125 having a sleevelike or bifurcated end-portion126 in which is movably disposed a portion of'a tripping rod 127, saidrod having its oneend-portion slidably disposed in the correspondinglyperforated up er end-portion 128 of the post 116 and aving pinned orotherwise secured uponsaid rod, between the end of the tripping arm 125of the pawl and the said end-portion 128 a collar or enlarge,- ment, as129. Mounted in the previously mentioned bearing-portions 67 and 68 is apin or rod 130, and oscillatorily mounted upon said pin or rod 130 aredownwardly extending perforated ears or bearing-mem bers 132 of asuitably formed tripping armature 131 having a. portion 133'locateddirectly above the disk or plate 60 which is carried by the enlargement37 of the stem or rod 35, and which disk or plate 60 attracts the saidportion 133 when the stem or rod-35 and its enlargement 37 and said diskor plate 60 become an electromagnet. One of the said ears or bearingmembers 132, as will be seen from an inspection of Fig. 5 of thedrawings, extends in a downward direction and is of such length, as at134, that it acts in the manner of a crank, said extension 134 carryinga pin 135 with which is oscillatorily connected the perforatedendportion 136 of the previously mentioned tripping rod 127.

At or near the other perforated ear or bearing-member 132, the saidtripping armature .131 is formed with a laterally perforated extension,as 137, in which is a pin 138, upon the extending portion of which isscrew-threaded rod or stem 145, said rodor stem bein nut 146 and piece147.

Secured to said nut 146 is an adjusting tension spring 149, said springbeing also attached-to said link 141. Mounted upon said rod or stem 145is a jamb-nut 148,

capable of adjustment in a aving a manipulating fingerwhich is adaptedto be screwed against the face of the bracket-member 143 so as to lockthe parts in their fixed adjusted positions, as will be clearlyunderstood. Suitably connected with the clamping element is aleading-out wire or cable 150.

Having in the foregoing description set forth the construction of thecircuit-breaker, and also the general arrangement ofthe several devicesand parts, we will now set forth, briefly, the operation of the severaldevices and parts of the circuit-breaker.

Under normal initial conditions the several devices and parts of thecircuit-b'reaker-are in the relative positions indicated in Figs. 1 and2 of the drawings, the various parts being set and held in such amanner, that the two contact-tips 89 and 100 are in contactingengagement, as shown, and whereby a complete electrical circuit isestablished with the main line, through the wire or 'cable96, intoandthrough said contact-tips '89 and 100, thence through thecontact-lever or member 78, and through the clamping element 79, theshunt-wire or cable 81, and the clamping element 49 into and through thecopper layers 41 of the overload or blow-out coil 40, from which thecurrent passes into the clamping element 50 into and through theleading-out'wire orcable 150. to the main circuit-wire.

no dangerous overload in the completed circuit. When, however, thereoccurs such overload, the increase current in the over- This conditionexists as long as there i. Y

load or blow-out coil 40 sufiiciently magnetizes the core or rod 35, itsenlargement 37 and the diskor plate 60, so as to attract thetripping-armature 131. The pivotal and downward movement of saidarmature 131, thus produced, causes the trip ing rod 127 to be movedin-the direction 0 the arrow 2: in Fig. 5 of the drawings, therebyforcing the collar or enlargement 129 on said rod against the bifurcatedend 126 of the tripping arm 125-and causing a sufficient piv-' otalmovement of the previously mentioned bell-crank which throws theretaining oifset 119 out of its holding engagement with 5 the roller 73of the arm 71, as lndicated in Fig. 4. Simultaneously, the tensionspring 68 exerts its, pull, so that the several arms 72, 75 and 7 8assumethe positions indicated in said Fig. 4, with the electric circuitinterrupted or broken by the disen aged contact-tips 89 and 100, as willbe 0 early evident. To again set the parts of the appaing or breakingthe electric circuit, the han-- dle-lever124 is moved in the directionof the arrow w, see Fig. 1, thereby causing a stud or projection 151 onsaid handle-lever to ride agalnst the inclineor angular surface 153 of aprojecting member 152 extending from the side-edge of the arm 118, thusalso actuating the bell-crank, and causing the various-parts to assumethe'positions indicated in said Fig. 4 of the drawings.

From an inspection of Fig. 2 of the drawings, it will be seen, that themagnetic polepleces 31 and 112 provide a magnetic field across the gapformed by the separated contact-tips 89 and 100 and across the spacebetween the walls 104 and 105 of the blowout box 26, whereby the arcingproduced by the separating contact-tips and the generated gases will beforced by magnetic blowout, through said box, and from the opening ofthe same, outside of the upper box or casing-member 46.

tion of the lines of magnetic force are across the gap. between thewalls 104 and 105, through the pole-piece or block 112, through the arm113, across the air-space between the end-portion of said arm 113 andthe tripping armature 131, through the latter,

parts, as well as in the details of the .con-' struction of the saidparts without departing from the scope of the present invention'as setforth in the foregoing specification, and as defined in the clauses ofthe claims which are appended to the said specification. Hence, do notlimit my present invention to the exact arrangements and combinationsclamping element and one of said terminal Reterring again to said Fig.2, the direc- Of course I am aware that changes may of the said devicesand parts as described in the said specification, nor do I confinemyself to the exact details of the construction of the said parts, asillustrated in the ac-- companying drawings.

I claim 1. In an overload circuit-breaker, in combination with anoverload coil, and a pair of terminal-clamps with which the respectiveterminals of the coil are connected, a magneticcore connected with saidoverload 0011, a switch-arm -:oscillatorily mounted 'upon said core, aspring-controlled contact-lever connected with said switch-arm, acontacttip carried by said switch-arm, a fixed contact-tip with whichsaid first-mentioned contact-tip i normally in contact, a clampingelement carried by said contact-lever, an electrical series-connectionbetween said clamps, and a tripping means for releasing saidcontact-lever and breaking the electrical contact between saidcontact-tips.

2. In an overload circuit-breaker, in combination with an overload.coil, and a pair of terminal clamps with which the respective terminals,of the coil are connected, a magnetic core connected with said overloadcoil, a switch-arm oscillatorily mounted upon said core,aspring-controlled contact-lever, a means of pivotal connection betweensaid contact-lever and said switch-arm, a contacttip' carried by saidswitch-arm, a fixed contact-tip with which said first-mentionedcontact-tip is normally in contact, a clamping .element carried by said'contact-lever, an

electrical series-connection between said clamping element and one ofsaid terminal clamps, and a tripping means for releasing saidcontact-lever and breaking the electrical contact between saidcontact-tips.

3. In an overload circuit-breaker, in combination with'an overload coil,and a pair of terminal-clamps with which the respective terminals of thecoil are connected, a magnetic core connected with said overload coil,

a switch-arm oscillatorily mounted upon said core, a spring-controlledcontact-lever connected with said switch-arm, a contacttip carried bysaid switch-arm, a fixed contact-tip with which said fiI'St-IIIGIItIOHGdcontact-tip is normally in contact, a clamplng element carried bysaidcontact-lever, an electrical series-connection between saidclamping'element and one of said terminal clamps, and a tripping meansfor releaslng said contact-lever and breaking the electrlcal contactbetween said contact-tips, con: sisting -of a pivotally mountedtrippingarmature adapted to be attracted by the core of said overloadcoil, a releasing means normally in engagement with said switch-arm, andmeans between said releasing means and the tripping-armature foractuating said releasing means.

4;. In an overload circuit-breaker, in combination with an overloadcoil, and-a pair of terminal clamps with which the respective terminalsof the coil are connected, a magnetic core connected with said overloadcoil, a switch-arm oscillatorily mounted upon Said core, aspring-controlled contact-lever, a means of pivotal connection betweensaidcontact-lever and said switch-arm, a contact-tip carried by saidswitch-arm, a fixed contact-tip with which said first-mentionedcontact-tip is normally in contact, a clamping element carried by saidcontact-lever, an electrical series-connection between 'said clampingelement and one of said terminal clamps, and a tripping means forreleasing said contact-lever and breaking the electrical contact betweensaid contact-tips, consisting of a pivotally mounted trippingarmatureadapted to be attracted by the core of said overload coil, a releasingmeans normally in engagement with said switcharm, and means between saidreleasing means and the tripping-armature. for actuatingIsaid releasingmeans.

5. nan overload circuit-breaker, in combination with an overload coil,and a pair of terminal-clamps with which the respective terminals of the,coil are connected, a magnetic core connected with said overload coil,a switch-arm oscillatorily mounted upon said core, a spring-controlledcontact-lever connected with said switch-arm, a contact-tip carried bysaid switch-arm, a fixed contacttip with which said first-mentionedcontacttip is normally in contact, a clamping element carried by saidcontact-lever, an electrical series-connection between said clampingelement and one of said terminal clamps, and a tripping means forreleasing said contact-lever and breaking the electrical contact betweensaid contact-tips, consisting of a pivotally mounted tripping armatureadapted to be attracted by the core of said overload coil, an auxiliaryarm connected with and extending from said switch-arm, a pivotalldisposed and spring-controlled bellcran -pawl having one member inengagement with said auxiliary arm, and means between the other memberof said pawl and the 1tripping-armature for actuating said paw 6. In anoverload circuit-breaker, in combination with an overload coil, and a,pair of terminal clamps 'with which the respective terminals of the coilare connected, a magnetic core'connecte'd with said overload COIl,aswitch-arm oscillatoril mounted upon said core, a spring-control edcontact-lever, a means of pivotal connection between said contact-leverand said switch-arm, a contact- .tip carried by said switch-arm, a fixedcontact-tip with which said first-mentioned contact-tip 1s normally incontact, a clamping element carried by said contact-lever, an

electrical series-connection between said clamping element and one ofsaid terminal clamps, and a tripping means for releasing a saidcontact-lever and breaking the electri cal contact between saidcontact-tips, consisting of a pivotally mounted trippingarmature adaptedto be attracted by the core of said overload coil, an auxiliary armconnected with and extending from said switcharm, a pivotally disposedand spring-controlled bell-crank-pawl having one member in engagementwith said auxiliary arm, and means between the other member of said pawland the tripping-armature for actuating said pawl.

7. In an overload circuit-breaker, in com bination with an overloadcoil,-and a pair of terminal-clamps with which the respective terminalsof the coil are connected, a magnetic core connected with said overloadcoil, a switch-arm oscillatorily mounted upon said core, aspring-controlled contact-lever connected with said switch-arm, acontact-tip carried by said switch-arm, a fixed contacttip with whichsaid first-mentioned contacttip is normally in contact, a clampingelement carried by said contact-lever, an electrical series-connectionbetween said clamping element and one of said terminal clamps, and atripping means for releasing said contact-lever and breaking theelectricalcontact between said contact-tips, consisting of a pivotallymounted tripping-armature adapted to be attracted by the core of saidoverload coil, an auxiliary arm connected with and extending from saidswitch-arm, a pivotall disposed and spring-controlled bellcran -pawlhaving one member in engagement with said auxiliary arm, and meansbetween the other member of said pawl and the tripping-armature foractuating said pawl, comprising a slidable tripping rod, a collarmounted upon said rod for engagement with the last-mentioned member ofsaid pawl, a crank-extension carried by said I tripping-armature, and ameans of pivotal connect1on between said crank-extension and saidtripping rod.

8. In an overload circuit-breaker, in combination with an overload coil,and a pair of terminal clamps with which the respective terminals of thecoil are connected, a magnetic core connected with said overload coil,

a switch-arm oscillatorily mounted upon said core, a spring-controlledcontact-lever, a means of pivotal connection between said contact-leverand said switch-arm, a contacttip carried by said switch-arm, a fixedcontact-tip with which said first-mentioned contact-tip is normally incontact, a clamping element carried by said contact-lever, an electricalseries-connection between said clamping element and one of said terminalclamps,

and a tripping means for releasing said contact-lever and breaking theelectrical I contact betweensaid contact-tips, consisting of a pivotallymounted tripping-armature adapted to'be attracted by the core of saidoverload coil, an auxiliary arm connected with and extending'from saidswitch-arm, a pivotally disposed and spring controlled bell-crank-pawlhaving one member in engagement with said auxiliary arm, and meansbetween the other member of said pawl and the tripping-armature foractuating said pawl, comprisin a slidable tripping rod, a collar mountedupon said rod for engagement with the last-mentioned member of saidpawl, a crank-extension carried bysaid tripping-armature, and a means ofpivotal connection between said crankextension and said tripping rod.

9. In an overload circuit-breaker, in combination with an overload coil,and a pair of terminal clamps with which the respective terminals of thecoil are connected, 'a magnetic core connected with said overload coil,a supporting plate having an'opening into and through which a portion ofsaid core projects, a bearing member upon said plate, a perforated lugextending from one of said a bearing members, a rod receiving guidepostalso upon said plate, a handle-lever having a hub-portion oscillatorilymounted upon the core-portion above said late, a perforated lugextending from said hubportion, a switch-arm also oscillatorily mountedupon said core-portion, a contactlever, a'means of pivotal connectionbetween said contact-lever and said switch-arm, a contact-tip carried bysaid switch-arm, a fixed contact-tip with which said first-mentionedcontact-tip is normally in contact, a clamping element carried by saidcontactlever, an electrical series-connection between said clampingelement and one of said terminal clamps, a coiled spring attached at oneend to said contact-lever and at its other end to the perforated lugextending from one of the bearing-members of said plate, atripping-armature pivotally mounted between the bearing-members of saidplate, an auxiliary arm connected with and extending from saidswitch-arm, a bell-crank-pawl pivotally mounted upon said plate, acoiled spring attached at one end to the perforated lug of saidhandle-lever and at its other end with one of the members of said pawlfor forcing said member in engagement withsaid trippingarmature foractuating said rod.

10. In an overload circuit-breaker, in combination with an overloadcoil, and a pair of terminal clamps with which the respective terminalsof the coil are connected, a mag netic core connected withsaid overloadcoil,

a supporting plate having an opening into forated lug extending fromsaid hub-portion, a switch-arm also oscillatorily mounted' upon saidcore-portion, a contact-lever, a means of pivotal connect1on betweensaid contact-lever and said switch-arm, a contacttip carried by saidswitch-arm, a fixed contact-tip with which said first-mentionedcontact-tip is normally in contact, a clamping element oarried by saidcontact-lever an electrical series-connection between said clampingelement and one of said terminal clamps, a coiled spring attached at oneend to said contact-lever and at its other end to the perforated lugextending from one of the bearing-members of said plate, atripping-armature pivotally mounted between the bearing-members of saidplate, an auxiliary arm connected with and extending from saidswitch-arm, a bell-crank-pawlivotally mounted upon said plate, a coiledspring attached at one end to the perforated lug of said handle-leverand at its other end with one of the members of said pawl for forcingsaid member in engagement with said auxiliary arm, a tripping rodslidably disposed in the rod-receiving guide-post of said plate, acollar mountedupon said rod for engagement with the other member of saidpawl, a crank-extension carried by said tripping-armature, and a meansof pivotal having an opening, one of said compartments providing ablow-out chamber, and the end-,

wall. of said casing forming part of said chamber being likewiseprovided with an opening, combined with a circuit-breaking -mechanismhaving a portion thereof extending through the opening in saidpartitionwall, an arcing-box located in said blow-out chamber, said boxhaving open end-portions, one of said end-portions projecting from theopening in said end-wall of the easing, and the said circuit-breakingmechanism being provided with separable contacttips located within saidarcing-box.

12. In an overload circuit-breaker, a casing having a partition-wallarranged to provide two compartments, said partition-wall having anopening, one of said compartments providing a blow-out chamber, and

the end-wall of said casing forming art of said chamber being likewiseprovide with an opening, combined with a circuit-breaking mechanismhaving a portion extending through the opening in said partition-wall,an arcing-box located in said blow-out chamher, said box having openend-portions,.one

of said end-portions projecting from the 4 lower member having a topproviding a base for the upper box-member, said upper boxmember having apartition-wall arranged to provide two compartments, said partitionwallhaving an opening, one of said compartments providing a blow-outchamber, and the end-wall of said upper box-member forming part of saidblow-out chamber being likewise provided with an opening, a magneticfield-element within said lower box-member, and an overload coil mountedupon said field-element, a second magnetic field-member located withinthe blow-out chamber of said upper box-member, combined with acircuit-breaking mechanism located within said upper box-member having aportion extending through the openin in said partition-wall, andprovided wit separable contact-tips located in said blowout chamber. 1

14. In an overload circuit-breaker, a lower box-member and an upperbox-member, said lower member having a top providing a base forthe u perbox-member, said upper boxmember having a partition-wall arranged toprovide two compartments, said partitiom wall having an opening, one ofsaid compartments providing a blow-out chamber, and the end-Wall of saidupper box-member forming part of said blow-out chamber being likewiseprovided with an opening, a magnetic field-element within said lowerbox-member, and an overload coil mounted upon said field-element, asecond magnetic field-member located within the blow-out chamber of saidupper box-member, combined with a circuit-breakingmechanism locatedwithin said upper box-member having a portion extending through theopening in c said partition-wall, an arcing-box located in said blow-outchamber, said box having open end-portions, one of saidend-portionsprojecting from the opening in said end-wall of the upperbox-member, and the said circuitbreakin mechanism being provided withseparab e contact-tips located within said arcing-box.

15. In an overload circuit-breaker, a lower box-member and an upperbox-member, said 'lower member'having a top providing a base cate insaid blow-out chamber, and a deflector-element extending from eachcontacttip toward the opening in the end-wall of said upper box-member.

16. In an overload circuit-breaker, a lower box-member and an upperbox-member, said lower member having a top providing a base for theupper box-member, said upper boxmember having a partition-wall arrangedto provide two compartments, said partitionwall having an opening, oneof said compartments providing a blow-out chamber, and the end-wall ofsaid upper box-member forming part of said blow-out chamber beinglikewise provided with an opening, a.

magnetic field-element within said lower box-member, and an overloadcoil mounted upon said field-element, a second magnetic field-memberlocated within the blow-out chamber of said upper box-member, com-.

bined with a circuit-breaking mechanism located within said upperbox-member having a portion extending through the opening in saidpartition-wall, an arcing-box located in said blow-out chamber, said boxhaving open end-portions, one of said end-portions projecting from theopening in said end-wall of the upper box-member, a pair of separablecontact-tips located within said arcing-box, and a deflector-elementextending from each contact-tip toward the opening in said arcv ing-box.V

In testimony that I claim the invention set forth above I have hereuntoset my hand this 13 day of August, 1919.

EDVARD M. MO'IJLER.

Witnesses:

FREDK. C. FRAENTZEL, BARBARA W. SUTIERIJN.

said dpartition-wall, a pair of contact-tips lo-

